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Southeast Regional Land Cover Change Report1996–2010
About This ReportThe Southeast Regional Land Cover Change Report, 1996–2010, is the first in a series of regional reports that
summarize the land cover status of the coastal United States in 2010 and land cover changes over the previous
decade and a half. This report provides an overview of key findings using reader-friendly maps and graphics.
About the Coastal Change Analysis ProgramSatellite imagery is a great way to get a big-picture view of the cumulative impacts of changes along our nation’s
coasts. The Coastal Change Analysis Program (C-CAP) within the National Oceanic and Atmospheric Administration
(NOAA) Office for Coastal Management produces nationally standardized land cover and land cover change
information for coastal regions of the United States, including the Southeast, using multiple dates of satellite
imagery. C-CAP’s data products provide inventories of coastal intertidal areas, wetlands, and adjacent uplands at
approximately five-year intervals. This information helps to support decision-making about coastal resources and
communities. The raster-based maps generated by C-CAP serve as a baseline for studies of coastal changes and
evaluations of past or future management actions.
To learn more about the C-CAP data products used in this report and to access the data sets, please visit
www.coast.noaa.gov/digitalcoast/data/ccapregional.
About the NOAA Office for Coastal Management NOAA’s Office for Coastal Management works at the center of the nation’s coastal management efforts. From
implementing the National Coastal Zone Management Program to providing technical assistance to coastal
communities through the Digital Coast, the organization strives to help the nation’s coastal communities prosper in
the face of numerous natural and man-made challenges. To learn more, visit the website at www.coast.noaa.gov.
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
THE SOUTHEAST COASTAL REGION covers almost 98,000 square miles and extends from North Carolina to the
southern end of Miami, just north of the Florida Keys. The region includes parts of North Carolina, South Carolina, Georgia, and Florida. Extensive forest, riverine, estuarine, marsh, and barrier-island systems are present, as well as mangroves and coral reefs. Commercial and recreational fisheries are an important economic driver and part of the region’s social fabric. The states of the Southeast service cargo and passenger ships with facilities that include some of the country’s largest and fastest-growing container ports. Natural and human-influenced hazards to the region include thunderstorms and tornadoes, floods and debris flows, earthquakes, tsunamis, drought, wildfires, winter storms, subsidence, saltwater intrusion, coastal erosion, and tropical storms.
The population along the coast of the Southeast states continues to grow rapidly. Thirty-seven percent of the 43 million people in these states live in coastal counties bordering the Atlantic Ocean. The expansion of recreation and tourism, residential development, service industries, and commercial space has transformed the social, economic, and physical landscape. The demand on natural resources has increased, including water for residential, agricultural, industrial, and recreational uses. Climate change impacts and degraded water quality are also concerns for natural and human communities in the region.
Many types of land cover, such as forest, wetland, and agriculture, occur in the Southeast, and the amount of each land cover type changes over time. Using images and data collected by satellites, NOAA’s Coastal Change Analysis Program (C-CAP) measured the area of each land cover type gained or lost from 1996 to 2010. In this report, 22 land cover classes are grouped into eight general categories: developed, agriculture, grass, shrub, upland forest, wetland, barren, and water.
The coastal Southeast is composed of nine major drainages, indicated on the map by different colors. Thin gray lines indicate boundaries of smaller watersheds.
Location of the Southeast region (red) within the Coastal Change Analysis Program’s mapping coverage area (dark gray) in the contiguous United States.
1
INTRO
DU
CTION
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
LAN
D C
OVE
R
This map shows the distribution of land cover types in the Southeast region in 2010.
2
Cultivated Crops
Pasture/Hay
Grassland/Herbaceous
Shrub/Scrub
Deciduous Forest
Evergreen Forest
Mixed Forest
Unconsolidated Shore
Bare Land
Open Water
Palustrine Forested Wetland
Palustrine Shrub/Scrub Wetland
Palustrine Emergent Wetland
Estuarine Forested Wetland
Estuarine Shrub/Scrub Wetland
Estuarine Emergent Wetland
Developed, High Intensity
Developed, Medium Intensity
Developed, Low Intensity
Developed, Open Space
Palustrine Aquatic Bed
Estuarine Aquatic Bed
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
Wetland
28% 18.4%
Forest
30,000
25,000
20,000
15,000
10,000
5,000
0
6,967
Developed
7.1%
10,216
Agriculture
18.9%
435
18,511
Shrub
10.4%
3,638
Barren
0.4%
17,965
Water
13.0%% of Basin
Area
(mi2 )
27,394
12,695
Grass
3.7%
Each block represents 1% of the total area of the Southeast region.
IN 2010, WETLANDS (28%), UPLAND FOREST (19%), AND AGRICULTURE (18%) were the most common categories of land cover in the region, accounting for approximately two-thirds of the area. The next most
common cover types were water (13%), shrub (10%), and development (7%). Less than 1% of the area was classified as barren.
The 22 land cover classes in the Southeast region have been grouped into eight major categories that are displayed in the map graphic to highlight their relative distribution in 2010. More detailed information about these eight categories is displayed in the bar chart.
33
= 97,800 square miles=978 square miles
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
FROM 1996 TO 2010, LAND COVER changed on 14,420 square miles, or almost 15%, of the Southeast region. Areas of change
were most common in counties inland from those most shore adjacent, particularly in southern South Carolina and Georgia west of Brunswick. Flagler County, Florida, (north of Daytona Beach) also had a high percentage of change during this period. Much of this change is associated with silviculture activities, common in timber management in the southeastern U.S.
With a loss of 3,563 square miles, upland forest was the land cover with the greatest net decrease in area. Shrub (2,470 square miles) and development (1,134 square miles) had the largest net increases.
TOTAL CHANGE IN LAND COVER
Net change per land cover category from 1996 to 2010. Arrows indicate the net loss or gain in each land cover category.
Total Area of Change Equivalent to
6,998,434Football Fields
1 Football Field Every
1 minute
+1,134 mi2
Developed
+2,470 mi2
Shrub
+156 mi2
Barren
-510 mi2
Wetland
+82 mi2
Water
+617 mi2
Grass
–386 mi2
Agriculture
–3,563 mi2
Forest
AREA OF CHANGE
14,420 square miles
15% OF REGION
4
25 to 40%
20 to 25%
15 to 20%
10 to 15%
0 to 10%
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
5
IN 2010, DEVELOPMENT accounted for 7% of the Southeast. This development is concentrated in
areas surrounding the large metropolitan areas of Miami, Orlando, and Jacksonville in Florida. Developed areas in the rest of the Southeast tend to follow the coast north from Florida through Savannah, Georgia; Charleston and Myrtle Beach, South Carolina; and Wilmington, North Carolina. Several cities along the inland boundary of this region also show development, including Fayetteville, North Carolina; Columbia, South Carolina; and Augusta and Macon, Georgia.
DEV
ELOPED
2010 development map for the coastal Southeast region of the United States. This map depicts intensity of development.
DEVELOPED AREA
6,967 square miles
7% OF REGION
Developed, High Intensity
Developed, Medium Intensity
Developed, Low Intensity
Developed, Open Space
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
Shrub
200
250
300
350
200
150
100
50
0
Area
(mi2 )
Agriculture Forest Wetland
305295
Developed*
74
Grass
67
Barren
39
243
Water
5
FROM 1996 TO 2010, THE AMOUNT OF DEVELOPED AREA increased by 1,134
square miles, or an almost 20% rate of growth. More than 70% of this new development was classified as low intensity and open space developed, which typically includes suburban and rural features such as parks, golf courses, and housing with large lawns. Florida, which contains the largest cities and most development in the region, added the greatest area of new development during this period. Areas surrounding the cities of Orlando, Miami, Savannah, Charleston, and Myrtle Beach are all prominent in the maps of developed change seen here.
New development across the Southeast during the 14-year time period was fairly evenly distributed on lands previously categorized as agriculture (26%), upland forest (25%), wetland (21%), and shrub land (17%). Development intensity increased on 74 square miles of already developed land; this type of change is commonly associated with increasing density of housing or infill development within city limits.
INCREASE IN DEVELOPED AREA
6
Increase in Developed Area Equivalent to
549,777 Football Fields
1 Football Field Every
13 minutes
This bar graph shows the area of each land cover that was converted to development between 1996 and 2010.* Increases in development intensity
LAND COVER CONVERTED TO DEVELOPED AREA
Square Miles
50 to 76
30 to 50
15 to 30
5 to 15
0 to 5
square miles1,134
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
7
These images of metropolitan areas within the Southeast region show patterns of new development (red) and increased density or infill development (yellow). This development often forms a halo pattern around a preexisting city core, reflecting the expansion of major roads and population growth away from the downtown. Background images: Esri
Orlando, FloridaMyrtle Beach, South Carolina
Charleston, South Carolina Savannah and Brunswick, Georgia
Increased Intensity New Development
HIGHLIGHT: METROPOLITAN DEVELOPMENT TRENDS
Pre-1996 High Intensity Pre-1996 Moderate Intensity
50 to 76
30 to 50
15 to 30
5 to 15
0 to 5
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
IN 2010, FOREST covered 35% of the Southeast region, including 19% upland forest and
16% wetland forest. While this report thus far has placed wetland forest types in the wetlands category, this section considers upland and wetland forests together for a more comprehensive view. The Southeast is fairly consistently forested, especially north of the Everglades and the dominant agricultural landscape of southern Florida.
FORESTED AREA
34,267 square miles
35% OF REGION
FORE
ST
8
2010 forest map for the Southeast. This map depicts three upland forest categories and two wetland forest categories.
Deciduous Forest
Evergreen ForestEstuarine Forest
Mixed Forest
Palustrine Forested Wetland
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
FROM 1996 TO 2010, 8,525 SQUARE MILES OF FOREST changed to other types of land cover (above left), and 1,852
square miles of other land cover changed to forest (above center). The result was a net loss of over 6,673 square miles of forest; most of these changes occurred throughout the region, except in the southern half of Florida.
FOREST AREA LOST 8,525 square miles
FOREST AREA GAINED 1,852 square miles
+ =
NET CHANGE IN FOREST AREA
40 to 60
20 to 40
10 to 20
5 to 10
0 to 5
100 to 169
60 to 100
30 to 60
15 to 30
0 to 15
9
Decrease in Forest Area Equivalent to
3,229,732Football Fields
1 Football Field Every
2 minutes
square miles6,673
Square MilesSquare Miles Square Miles
Silviculture Activities in Forest Lands
Timber activities (i.e., silviculture) often result in a patchwork appearance in the landscape. The C-CAP change map on the lower left shows forest cuts (red) and regrowth from previous cuts (green) that have occurred during this period in a portion of central Florida. The image on the right is satellite imagery of the same area.
-100 to -149
-50 to -100
-30 to -50
-15 to -30
0 to -15
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
MOST OF THE LOSSES IN FOREST LAND COVER consisted of changes from forest to grass or
shrub (89% of all forest losses, combined). At the same time, most gains came from areas that were formerly grass or shrub and changed to forest (98% of all gains, combined). This pattern suggests that many of the region’s forested areas are undergoing transitions that
do not result in permanent loss. However, losses of forest to development are more likely to be permanent. Approximately 467 square miles of forest were lost to development during the study period, accounting for 7% of the net losses. Of these losses, 295 square miles were upland forests and the remaining 172 square miles were wetland forests.
+ = NET CHANGE OF FOREST TO OTHER LAND COVER
FOREST GAINED FROM OTHER LAND COVER
FOREST LOST TO OTHER LAND COVER
These graphs show the categories of land cover that forests were lost to or gained from, along with the resulting net change between each of these categories and forests between 1996 and 2010.
HIGHLIGHT: EFFECTS OF PROTECTED LANDS ON FOREST LAND COVER U.S. Fish and Wildlife Service National Wildlife Refuges and other managed lands often protect forests from timber management activities (i.e., silviculture). The Great Dismal Swamp (left) shows timber losses and significant change in forests occurring up to the boundaries of the refuge. A similar pattern can be seen in the Pocosin Lakes National Wildlife Refuge (right), but the change was caused by fire. The impacts were less severe within the refuge boundary, primarily because of a fire break and the refuge’s restoration of 7,500 acres of wetlands and hydrologic function.
10
Area
(mi2 )
0
-5000
-4000
-3000
-1000
1000
-2000
2000
Agric
ultu
re
Deve
lope
d
Gras
s
Shru
b
Barre
n
Wat
er
Agric
ultu
re
Deve
lope
d
Barre
n
Wat
er
Agric
ultu
re
Deve
lope
d
Barre
n
Wat
er
Shrub
Grass
Shrub
Grass
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
11
APPROXIMATELY 28% OF THE SOUTHEAST REGION was covered by
wetlands in 2010. The region is dominated by freshwater, primarily woody wetlands, but also includes significant amounts of estuarine wetlands, which occur in proximity to the coasts and tidal waterways. All wetland types are most prominent along the low-lying areas of the coasts, commonly referred to as the Lowcountry.
WETLA
ND
WETLAND AREA
27,394 square miles
28% OF REGION2010 wetland map for the coastal Southeast. This map depicts seven wetland categories.
Palustrine Forested
Palustrine Emergent
Estuarine Forest
Estuarine Shrub/Scrub
Estuarine Emergent
Palustrine Shrub/Scrub
Unconsolidated Shore
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
TOTAL WETLAND AREA ACROSS THE REGION remained relatively stable from 1996 to 2010, with a loss of 1,003 square miles (above left) and a gain
of 493 square miles (above center). Some areas had a net gain and others had a net loss (above right). The overall net change was a decrease of 510 square miles. This is a significant area, but it represents less than a 2% net loss of total wetlands present in 1996.
Freshwater forested wetlands such as cypress swamps and bottomland hardwoods are the most common type (58%) of wetland. Twenty-two percent of the region’s wetlands are emergent wetlands, including salt marshes.
WETLAND AREA LOST 1,003 square miles
WETLAND AREA GAINED 493 square miles
+ =
NET CHANGE IN WETLAND AREA
5 to 15
0 to 5
0 to -5
-5 to -15
-15 to -40
20 to 43
10 to 20
5 to 10
2.5 to 5
0 to 2.5
20 to 42
10 to 20
5 to 10
2.5 to 5
0 to 2.5
12
square miles
510
HIGHLIGHT: WETLAND CHANGES FROM HUMAN ACTIVITIESCoastal areas are popular places to live, and account for much of the nation’s population. In the Southeast, development is a major source of wetland loss. The images on the right show the appearance of a new neighborhood on the south side of Miami, Florida, on Biscayne Bay.
Another example of human influence is visible in the image on the left in the Emeralda Marsh Conservation Area (Lake County, Florida). These historical wetlands were diked, drained, and converted to agriculture and pasture fields in the 1940s. The St. Johns River Water Management District purchased seven parcels between 1991 and 1993 and began restoration efforts in 1994. By 2010, the former fields had reverted primarily to wetland vegetation (yellow).
Square Miles Square Miles Square Miles
Gai
nLo
ss
SOUTHEAST REGIONAL LAND COVER CHANGE REPORT, 1996–2010
WETLANDS IN THE SOUTHEAST REGION were primarily lost to development (49% of all
wetlands lost), while nearly all wetlands gained came from agricultural features (57% of gains) and open water (39% of gains). The losses were most heavily concentrated in and around Orlando, Florida; in Horry County, South Carolina (home of Myrtle Beach); and outside of Miami, Florida, just north of the Florida Keys. Gains seen in the counties surrounding Gainesville and Ocala, Florida, are mostly the result of lake levels being low and the formerly submerged soils being exposed. This is also true of gains seen along the southern shore of Lake Okeechobee in Palm Beach County, though some of the gains in this area are from new water treatment facilities.
In addition to mapping areas of direct wetland loss, C-CAP also maps changes between the various types of wetlands through time. In the Southeast region, 3,096 square miles of changes to wetlands were mapped. As discussed in the forest section of the report, many of these changes were associated with timber, or silviculture, activities of forest cuts and regrowth though time. Certain areas were ditched and drained to support forestry, but these changes—perhaps from wetland to upland—are difficult to confirm without field visitations or more detailed information. While not reported here as losses, some of these changes do typically occur and could be reviewed to determine the additional amount or specific locations of losses.
+ = NET CHANGE BETWEEN WETLAND AND OTHER LAND COVER
WETLAND GAINED FROM OTHER LAND COVER
WETLAND LOST TO OTHER LAND COVER
These graphs show the categories of land cover that wetlands were lost to or gained from, along with the resulting net change between each of these categories and wetlands between 1996 and 2010.
13
Area
(mi2 )
0
-300
-100
100
200
-200
Agric
ultu
re
Barre
n
Wat
er
Agric
ultu
re
Deve
lope
d
Barre
n
Wat
er
Agric
ultu
re
Barre
n
Wat
er
Developed
Developed